酸法脱酰胺结合酶解制备米蛋白肽及其与亚铁螯合工艺研究

Analysis on Acid Preparation of Rice Protein and Process of Enzymatic Hydrolysis Peptides to Ferrous Chelate

采用米蛋白为原料,经酸法脱酰胺、蛋白酶酶解后,以FeCl_2作为铁源制备米蛋白肽亚铁螯合物。结果表明,碱性蛋白酶对米蛋白的水解效果最好,经4 h酶解后蛋白的水解度和蛋白肽得率分别达到23.4%和73.4%。酸法脱酰胺处理能有效提高米蛋白肽的得率。采用0.4 mol/L HCl在95℃处理3 h制备的脱酰胺米蛋白,其水解度和蛋白肽得率分别达到27.1%和92.6%;单因素试验表明反应温度、pH和质量比均对米蛋白肽亚铁螯合物的产品得率和螯合能力有显著影响;米蛋白肽与亚铁盐的最佳螯合工艺条件为:反应温度50℃、蛋白肽与亚铁盐的质量比2:1、pH 6.5;在此条件下其产品得率为65.2%,亚铁螯合能力最大为21.6 mg/g。

In this paper, rice protein as the raw material with acid deamidation and proteolysis enzymolysis was used to prepare the rice protein peptides ferrous chelate, and FeC12 was adopted as the iron source. The results showed that Alcalase was the best protease to hydrolyze rice protein. The degree of hydrolysis and the yield of protein pep- tides after 4 hours＇enzymolysis reached 23.4% and 73.4% , respectively. The yield of rice protein peptides was effectively improved after acid deamidation. The deamidation - protein was obtained in the conditions （0.4 mol/L HC1, temperature at 95 ℃ and time 3 h）. Under these conditions, the degree of hydrolysis and the yield of protein peptides reached 27.1% and 92.6%. Single factor experiment showed that temperature, pH and mass ratio had sig- nificant effects on the yield and iron - chelating capacity of the rice protein peptides ferrous chelate. The optimal con- ditions for enzymatic hydrolysis peptides to chelate iron were showed as follows： temperature at 50 ℃, mass ratio in 2： 1, pH at 6.5. Under these conditions, the yield of this product was 65.2% and the maximum level of ferrous - chelating capacity was 21.6 mg/g.